Impact of tumor subsite on survival outcomes in oral squamous cell carcinoma: A retrospective cohort study from 2000 to 2019.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is responsible for high morbidity and mortality worldwide. Although the oral cavity encompasses different anatomical subsites, it is unclear whether subsite localization of carcinoma influences outcome. METHODS: This retrospective cohort study examined overall survival (OS), recurrence-free survival (RFS) and local recurrence-free survival (L-RFS) at different subsites by Kaplan-Meier survival curves. Cox proportional hazards regression analysis was performed to investigate the impact of subsite on overall death, locoregional recurrence, and local recurrence. RESULTS: The cohort included 1702 patients treated with curative intent for OSCC according to standardized national guidelines. The 5-year OS was superior in oral tongue to retromolar trigone as well as in both oral tongue and floor-of-mouth (FOM) compared to tumors involving multiple locations. The 3-year RFS in oral tongue and FOM was superior to tumors involving multiple locations, and in FOM compared to retromolar trigone. The 3-year L-RFS in oral tongue and FOM was higher than gingiva, retromolar trigone and tumors involving multiple locations. Adjusting for relevant covariables using oral tongue as reference, tumors involving multiple locations was the only category presenting higher risk for locoregional recurrence, while risk of local recurrence was higher in gingiva, retromolar trigone, hard palate and to tumors involving multiple locations. The study found no difference in risk of death between subsites. CONCLUSION: The study found differences in survival outcomes between subsites. After adjusting for covariables, subsite mainly had significant impact on local recurrence, with no distinct pattern of influence on overall death or locoregional recurrence.

The impact of tobacco smoking on survival of patients with oral squamous cell carcinoma: a population-based retrospective study.

BACKGROUND: This article aims to evaluate the impact of smoking status, accumulated tobacco exposure (ATE), and smoking cessation on overall- and disease-free survival (OS and DFS) of patients with oral squamous cell carcinoma (OSCC). MATERIAL AND METHODS: Patients with primary OSCC treated with curative intent between 2000 and 2019 in Copenhagen were included (n = 1808). Kaplan-Meier curves and multivariable Cox regression analyses were performed to compare the survival of patients with different smoking history. Interactions between ATE and (A) tumor subsite and (B) excessive alcohol consumption (EAC) on the survival were evaluated using multivariable Cox regression analyses with interaction terms. RESULTS: We included 1717 patients with known smoking status (62.8% males, median age: 64 years (IQR: 57-71 years)), who had a 5-year OS of 53.7% (95%CI: 49.8%-57.9%). Based on fully adjusted multivariable Cox regression analyses, significantly elevated hazard ratios (HRs) for OS and DFS were identified for current, but not former smokers, compared to never-smokers. An approximately linear relationship between continuous ATE and survival estimates was identified. ATE analyzed as a categorical variable showed significantly elevated HRs for OS of patients with all categories (060 PYs), however only for DFS of patients with >60 PYs, compared to 0 PYs. Furthermore, an unfavorable long-term prognosis was evident after >3.5 (OS) and >2.5 (DFS) years from diagnosis for patients who continued smoking compared to patients with smoking cessation at diagnosis. The survival estimates of patients with different tumor subsite and alcohol consumption differed with increasing ATE. CONCLUSION: Tobacco smoking (assessed as smoking status and ATE) was associated with inferior survival (OS and DFS) among patients with OSCC. Unfavorable long-term prognosis was significant for patients who continued smoking compared to patients with smoking cessation at diagnosis. The impact of ATE on survival of patients with OSCC may depend on the tumor subsite and/or alcohol consumption.

The Effect of Prophylactic HPV Vaccines on Oral and Oropharyngeal HPV Infection-A Systematic Review.

Human papillomavirus (HPV) imposes an increased risk of developing cervical, anal and oropharyngeal cancer. In the Western world, HPV infection is currently the major cause of oropharyngeal cancer. The effectiveness of HPV vaccines for oral or oropharyngeal HPV infection is yet to be determined. This study conducted a systematic literature search in Pubmed and Embase. Studies investigating the impact of HPV vaccines on oral or oropharyngeal HPV infection were enrolled. This review reports the relative prevention percentage (RPP), including a risk of bias assessment as well as a quality assessment study. Nine studies were included (48,777 participants): five cross-sectional studies; one randomized community trial study (RCT); one longitudinal cohort study; and two case-control studies. A significant mean RPP of 83.9% (66.6-97.8%) was calculated from the cross-sectional studies, 82.4% in the included RCT and 83% in the longitudinal cohort study. Further, two case-control studies that measured antibody response in participants immunized with HPV vaccines were included. Respectively, 100% and 93.2% of participants developed HPV-16 Immunoglobulin G (IgG) antibodies in oral fluids post-vaccination. Analysis of the studies identified a significant decrease in vaccine-type oral or oropharyngeal HPV infections in study participants immunized with HPV vaccines across study designs and heterogenous populations. Further, a significant percentage of participants developed IgG antibodies in oral fluid post-vaccination.